Band-chuck.



MID. HEYIVIAN.

BAND CHUCK.

APPLICATION FILED MAR 18. 1915.

1,15,2161 Patented 001. 26, 1915.

INVENTOR WITNESSES 3] Moses D. Hegmcm 1 ATTORNEYS 40 made of anysuitable materials, and the BAND-CHUCK.

Applicationfiled lvlareh 18,1915. Seria1 N0.15-,2 8l:

To all whom it may concern Be it known that I, Mosns D. HEYMAN, acitizen of the United States, and a resident ofithe city of New York,borough of Brook lyn, in the county of Kings and'State of New York, haveinvented a new and vImproved Band-Chuck, of which the following is afull, clear, and exact description;

Among the objects of the invention is to providea work holding chuck =ofa simple,

which, therefore, may be produced and at a comparatively lowcost. v 1

inother obj ect of the invention is to provide a chuck, theimmediate-holding porsold " tion of which is a flexible circular bandadapted to snugly engage practically all the way around the work beingturned, whereby all danger-of damaging the workbycrushing, indenting or.otherwise marring the same will bea-voided. Y I

A still furtherobj'ect of the invention is to provide. a jaw member orgripping-device, for a chuck adapted to be manipulated by the rotationof'a simple-member, means being provided to cause the "operation ofthegripping member for-its. purpose Without disturbing :the alinement ofthe work a i The: foregoing and other objects of th invention willhereinafter be more fully-Glee scribed and claimedand illustrated in,the drawings :forming a part ofmthislspecification in which likecharacters of reference indicate corresponding parts in :all' the yiews,andin which e r r, i

Figure'l is a vertical transverse section on the line 11 of F ig. 2; andFig 2; isa .verticalilongitudinal section on the line 2-r-2 of Fig. l.

The several of this device be relative sizes and proportions, as well asthe general design of themechanism, may be varied to a considerableextent withoutde= parting from the spirit of: the invention hereinaftermore fully described and/spa cificallyclaimed. V A i a r Referring moreparticularly to the drawings I show at 10 a casingof substantiallycylindrical form and carried concentrically upon an arbor l1 atone end;The other end of the casing is normally-closed byla face plate 12securedin place as by screws 13 tapped into the peripheral flange 14of:.the casing. The face plate 12is provided with a central opening 15.r e.

Specification of Letters Patent.

Patented Got. 26, 1 915.

The main gripping element of the chuck consists of a flexible band 16 ofany suitable strong elastic material and preferably faced with a layerof leather, felt or some other suitable cushioningmaterial 17 for thepurpose of preventing the abrasion or inarringof a pieceof work whichmay be finished orhighly polished at the end being held by-the device.

The band 16 is shown in its extended form or position and is adapted tobe contracted to cause it to gripthe work. If a bar, tube or rod of muchsmaller diameter is to be connected to thechuck, a bushing,indicated atB, of leather or other suitable material may be introduced, as shown in-Fig. 1, to act as a fillerbetween: the band and the WOI'lC. i

The means I prefer to employ to adjust the band to vary itscircumference includes a rotary shaft or boltH18v journaled in-bearingsl9 and 20 in the fiange 1i adjacent one side ofthe casing, said bolthaving right and left threads 21 and '22 adjacent itsmi ddle portionwith whichcooperate' a pair of blocks 23 and theadjacent end of theband16. Thebifurcated portion of eachlblookis provided with 24; :Thesebbcksextendninwardlytoward vertical slots 26, the long-en axes of which areatright angles to the direction of move ment of the blocks due to therotation ofthe bolt 18.. Connection between the blocks and the lugs 25is had through pins 27wvl1ich extend through the slots .of the blocksand through the lugs 25 in directions parallel to the axisofthe chuck,said pinssubstantially fitting the shorter diameters of the slots 26.InothernWords, with the movement of the blocks toward and fromeachotheralong the bolt, the pin'sc27 will be correspondingly moved inboth directions. There being no 10st motion, therefore, between thepinsand the lugs 25 orbetween the' pins and the blocks considered inthe. direction of movefeatures provided herein, such movement of thebottom portion of the. band would be greater than the decrease in radius'd'ueto the contraction of the band. In other words, with the lugs 25moved toward each other, there will not 'ordinarily follow thecorresponding inward movement thereof in accordance with the decrease inradius of-the band. To compensate for this circumstance, I "extend theends" of the pins into parallel grooves 29 formed in the opposed innerfaces oft'he front and rear portions of the'casi'ng'. Each of thesegrooves comprises two curves arrangedntaslight angle to each other, asshown in Fig. 1, the character of the curve and'the ain'ount ofanglebeing determined by" the extent a'nddirec'ti'on of movement of thepins toward each other." I1i 'the form indicated," the pins are 'Inovedupwardly slightly as they ,begidtheir" movement toward-'each other, dueto the fact that in-tlie open p0s i'tion of theband the'ends of the bandstand at consider'able distance below the actual circumference of the"band hence, when 'theppins b egin to meve toward each other,"'saidband"end's' 'have"a certain upward movement, but such movement continuedthere" is, due to the contraction of the c rcumference; a downwardmovementpf the pins asthey come close" to each -otherg The form' of thegrooves, therefore, 'is such that they compensate for the compoundmovements'of the pins, or, in bther words, "the grooves 'are sodesigne'dthat they positively cause the pins te eve in" such paths th'at the bandremains" always substantiallyfcon'centric'with'the casing. p "At 301showa'counterweight secured-in the bottom: of the asing as by means offascrew 31 to counterpoise the*w'eight "of-the bolt l8and' parts carriedtherebyg'ff'I-wish it to be understood the terms upward and downward?"andsimilar terms, eniplayed throughout the'specification areto beinterpreted 3 a "relative sense and fn 'o't as limitations."*'

p '53"" While "the work is adapted to be heldautomatic'ally' centeredthe mere {a dj Usitirieht of the band, yet it may be desirabldfundercertain circumstances, when the chuckisbeing operated at a high speedfor instance, for some positive means tolock the band concentric with"the"shaft *andf'casing. Hence, after the application of theba nd; tothe work, I may adjust a series-pf set scfews 32 radially intofcontaetWithfthe outerfsfirface of thebandto steady thesaine' and hold itpositively in centered positions T 9 While thforebingideseritionicoversfbut two lugs 25 connected to theband with acorresponding number of guide. 27, it! is obvious that under certaincircumstances or b jdi s-l my e d n e u de- P n vc ,t rwra i 'w t 582 6.a a a efls pei'ints. "As an illustratioii of such J Eddi tional guidefeatures, I show at 25 a guide lug securedto the middle portion of theband and having a guide pin 27 extending therethrough and guided along apair of straight radial slots 29. This construction may be used eitherwith or without the counterweight 30, and if the additional lug 25 isused, the intermediate set screw 32 may be shortened for coeperationwith the outer end of such lug.

I claim:

' 1511i a device of the character set forth, the combination of a casingcomprising a rear wall, a peripheral flange and a face plate parallel tothe rear wall and secured to the flange, said face plate having anopening concentricwith the casing, said face plate and'rear wall havinga pair of parallelgroo ves formed in 'tllBiPOPDOSGd inner faces, aflexible band constituting a gripping memberadjacentsaid face plateopening and surrounding the axis of the casing, and means guided alongsaid grooves to cause the ends of the band to approach or recede fromeach other. V I

In a device of the character set forth, the'combination of a hollowcasing, a flexibl'e gripping band mounted within and concentric withthe'casing, said band being split and having lugs extending from theadjacent ends thereof, and means coeperating with-the casing and actingupon said lugs to cause 'the'b and to expand or contract, said meansaeting'also tomaintain the band in its' co'ncen'tric relation to thecasing.

3.- In a devi ceof the character set forth, the combination of acircular casing, a split bandarrang'ed concentric coaxiallv with thecasing, a 'bolt journalcd in one SldG'Of the casing and having right andleft threads thereon, a lpa'irof blocks'connected to the ends'ofthebandand mounted upon the threaded portions of' the bolt whereby uponrotation of the bolt the band will be contracted or expanded, meansco6perating withsaid'band ends to maintain theband concentric with thecasing irrespective ,ofits circumferential adjustment.

adevice of the character set forth, the combination of a casing,'a splitband of: flexible material constituting a gripping member arrangedconcentrically of the easing, a bolt" journaled in the casing at oneside' -cf its center and in a' direction-transverse "to'it's' axis, saidbolt having right and left threaded portions, a pair of' blocks mountedupon said threaded portions of the boltand movable therebv toward orfrom each other upon rotation of the bolt in the easing, saidblockshaving slots formed in their inner en' ds witli the'longer axes ofthe slots perpendicular to the "direction of movement of theblocks, apairof lugs connected to the ends of the band, pins extending'throughthe lugs and through the block sl'ots, and'm eans acting positively uponthe pins to cause the band to remain in its concentric relation to thecasing irrespective of the changes in diameter of the band.

5. In a device of the character set forth, the combination of a hollowcylindrical casing, a flexible split gripping band arrangedconcentrically therein, means arranged Within one side of the casing toincrease or decrease the circumference of the band and maintain it inits concentric relation and a counterbalance secured in the other sideof the casing to counterpoise the Weight of said adjusting means. 7

6. In a device of the character set forth, the combination of a hollowcylindrical casing, a flexible gripping split band arranged therein,means acting through the side of the casing and upon the ends of theband to increase or decrease its effective circumference, and a seriesof set screws extending radially through the periphery of the casing andagainst the outer surface of the band to positively lock the same inconcentric relation to the casing.

In testimony whereof I have signed my name to this specification in thepresence of two subscribing witnesses.

MOSES D. I-IEYMAN.

Vitnesses GEO. L. BEELER, PHILIP D. RoLLHAUs.

Copies of this patent may be obtained for five cents each, by addressingthe Commissioner of Patents, Washington, D. C."

